Not about the 'science!' Question about ending SPOILER ALERT
The "science" is way too absurd so I'm not even going to try to figure out where they came up with their ideas.
BUT...I admit to not paying extreme attention to this movie, so I'd like a spoiler, please. At the end, the two survivors wind up in the ocean, sure no one will find them because their comms are out, etc. Then, more weird science, whales start circling on the surface, and there is great whooping and hollering. Divers go down, planes and ships circle. The last scene is the two of them talking about how they hope word will somehow get out about the sacrifices the others made to save the lives of the rest of the world. We know it will, because their boyish friend is all over the internet telling the story. Then it ends. So, are they not rescued? It seems very ambiguous to me.